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Fisher Transform

Ehlers DSP oscillator ehlers normalization momentum

Converts inputs to a nearly Gaussian probability distribution, creating sharp peaks at turning points.

Usage

Apply to normalized prices or oscillators to sharpen turning-point signals. The near-Gaussian output makes extreme values statistically significant and easy to trade.

Background

Ehlers introduces the Fisher Transform in Cybernetic Analysis (2004) to convert any bounded indicator into a Gaussian normal distribution. Values beyond ±1.5 signal statistically significant price extremes, sharper than raw oscillators.

Formula

\[ Fish(x) = 0.5 \times \ln\left(\frac{1 + x}{1 - x}\right) = \text{atanh}(x) \]

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